CHARACTERISTICS OF OSCILLATORY FLOW OVER RIPPLE MODELS

Kiyoshi Horikawa, Syunsuke Ikeda

Abstract

The results of extensive laboratory investigations on the oscillatory flow over ripple models were presented. The ripple models were installed in an oscillatory flow flume. A two-dimensional lasser doppler velocimeter was utilized to measure the fine structure of flows in the vicinity of the whole length of a ripple model which was induced by various types of oscillatory flow. The results of measurements were displayed in the form of distributions of mean fluid velocity, stationary velocity, fluid turbulence intensity and Reynolds stress. By using these data the characteristics of oscillatory flow, such as the formation and decay of vortices, the generation of stationary velocity and the variation of kinematic eddy viscosity were discussed.